BRUMADINHO, Brazil — The Brazilian police on Tuesday arrested five people, including three employees of the giant mining company Vale, as part of an investigation into a dam rupture that left at least 84 dead and 276 missing.

The dam, filled with mining waste and sludge, burst on Friday afternoon, sending a tidal wave of mud crashing down on homes in the town of Brumadinho in southeastern Brazil. The torrent also struck Vale administrative buildings, including the company cafeteria.

The other two people arrested were engineers working for the Brazilian subsidiary of the German industrial testing company TÜV Süd, which conducted two inspections of the Brumadinho dam last year, the most recent in September, according to both Vale and TÜV Süd. The subsidiary carried out an inspection of the dam’s safety in September, it said, though it refused to comment further, citing the continuing investigation.

Brazilian federal and state prosecutors said in a news release that the five arrests, as well as seven search warrants that were executed, were “aimed at investigating criminal responsibility for the rupture.” The arrests were focused on individuals who had been involved in the most recent safety and environmental survey, which concluded that the dam was “stable.”

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Graves dug for the burial of victims of the dam disaster in Brumadinho, Brazil.CreditAntonio Lacerda/EPA, via Shutterstock

According to the arrest warrant, the five men will be held for an initial 30 days and could be charged with participating in homicide, false representation and environmental crimes. It called for the seizure of documents and mobile phones.

The Vale employees arrested were directly involved in and responsible for the mining enterprise and its licensing, according to prosecutors. The other two people arrested had “attested to the stability of the dam on a recent date.”

In Brazil, independent auditors verify the safety of dams through regular inspections and analysis of written records. But according to experts, the certification process is flawed because the mining companies select and pay the auditor — creating a possible conflict of interest — and provide all of the documentation that inspectors base their analyses on.

The arrest warrant did not cite specific evidence beyond the stability certification and the dam collapse itself, saying it wasn’t believable that such large dams “managed by one of the biggest mining companies in the world, suddenly ruptured without giving any indication of vulnerability.”

At a news conference late Tuesday, Fabio Schvartsman, the chief executive of Vale, said the company had decided to close the remaining 10 dams built in the same manner as the Brumadinho dam, and would stop operations at all of the mine complexes where they were located until they had been fully decommissioned. Such “upstream” dams, which use mining waste and tailings as banks for the dam, are cheaper than dams built with earth and rocks, but considered less safe.

“This is an unprecedented effort by a mining company,” Mr. Schvartsman said, to provide “an exacting response that corresponds to the enormous tragedy that we had in Brumadinho. He added that the decommissioning process could take between one and three years.

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The police taking away evidence after the arrest of two engineers in São Paulo on Tuesday.CreditFernando Bizerra Jr/EPA, via Shutterstock

In a statement posted to Twitter, Vale said that it was fully cooperating with the authorities: “Vale will continue to support the investigations in order to determine the facts, in addition to the unconditional support to the families #Brumadinho.”

Vale faces mounting anger and public pressure as the death toll rises and rescue workers acknowledge that efforts to dig through the sludge are focused more on finding bodies. The company also jointly owned another upstream dam 75 miles away, near the town of Mariana, that burst three years ago, killing 19 people and unleashing one of the worst environmental disasters in Brazilian history.

In Brumadinho, about 100 people gathered in the local cemetery on Tuesday morning to mourn the death of Duane Moreira, 33, who was operating a train in the mining compound when the dam broke. His wife, two sisters and mother wept over his closed coffin. Juarez Oliveira, a local priest, called Mr. Moreira’s death a murder.

“We need to resuscitate hope,” he said. “There is a lot of hate, but we need to find oxygen.”

Luciano Siani, the chief financial officer of Vale, announced that the company would give the families of those killed 100,000 reais each, or around $26,800. Judges have ordered the company to set aside 11 billion reais, about $2.9 billion, to pay damages caused by the dam collapse.

The announcements have done little to console residents of Brumadinho. Mr. Moreira’s mother, Rosângela de Mattos, is not only mourning her son but is also unsure of the fate of her sister, who was working at the mining complex on Friday. She has not been heard from since the dam collapsed.

“They can sell the whole company and give us the money,” Ms. de Mattos said. “But nothing will pay for the lives of my son and my sister.”